Python讲解之对象转XML方法详解

# -*- coding:UTF-8 -*-

'''''

Created on 2010-4-20

@author: 忧里修斯

'''

import xml.etree.ElementTree as ET

import xml.dom.minidom as minidom

from addrbook.domain import Person

class Converter(object):

  '''''

     实现Python对象与xml之间的相互转换

  '''

  root = None#根节点

  def __init__(self):

    pass

  @staticmethod

  def createRoot(rootTag):

    '''''

          创建根节点

    '''

    root = ET.Element(rootTag)

    return root

  @staticmethod

  def getXmlString(element,defaultEncoding='utf-8'):

    '''''

          根据节点返回格式化的xml字符串

    '''

    try:

      rough_string = ET.tostring(element, defaultEncoding)

      reparsed = minidom.parseString(rough_string)

      return reparsed.toprettyxml(indent=" " , encoding=defaultEncoding)

    except:

      print 'getXmlString:传入的节点不能正确转换为xml，请检查传入的节点是否正确'

      return ''

  @staticmethod

  def classToElements(classobj,rootTag=None):

    '''''

          根据传入的对象的实例，根据对象的属性生成节点，返回由节点组成的列表

    classobj：对象的实例

    rootTag：根节点名称

    '''

    attrs = None#保存对象的属性集

    elelist = []#节点列表

    try:

      attrs = classobj.__dict__.keys()#获取该对象的所有属性(即成员变量)

    except:

      print 'classToElements:传入的对象非法，不能正确获取对象的属性'

    if attrs != None and len(attrs) > 0:#属性存在

      for attr in attrs:

        attrvalue = getattr(classobj, attr)#属性值

        #属性节点

        attrE = ET.Element(attr)

        attrE.text = attrvalue

        #加入节点列表

        elelist.append(attrE)

    return elelist

  @staticmethod

  def classToXML(classobj,rootTag=None):

    '''''

    Python自定义模型类转换成xml，转换成功返回的是xml根节点，否则返回None

    classobj：对象的实例

    rootTag：根节点名称

    '''

    try:

      classname = classobj.__class__.__name__ #类名

      if rootTag != None:

        root = Converter.createRoot(rootTag)

      else:

        root = Converter.createRoot(classname)

      elelist = Converter.classToElements(classobj, rootTag)

      for ele in elelist:

        root.append(ele)

      return root

    except:

      print 'classToXML:转换出错，请检查的传入的对象是否正确'

      return None

  @staticmethod

  def collectionToXML(listobj,rootTag='list'):

    '''''

              集合（列表、元组、字典）转换为xml，转换成功返回的是xml根节点，否则返回None

    '''

    try:

      classname = listobj.__class__.__name__ #类名

      root = Converter.createRoot(rootTag)

      if isinstance(listobj, list) or isinstance(listobj, tuple):#列表或元组

        if len(listobj) >= 0:

          for obj in listobj:#迭代列表中的对象

            itemE = Converter.classToXML(obj)

            root.append(itemE)

      elif isinstance(listobj, dict):#字典

        if len(listobj) >= 0:

          for key in listobj:#迭代字典中的对象

            obj = listobj[key]

            itemE = Converter.classToXML(obj)

            itemE.set('key', key)

            root.append(itemE)

      else:

        print 'listToXML：转换错误，传入的对象：'+classname+'不是集合类型'

      return root

    except:

      print 'collectionToXML：转换错误，集合转换成xml失败'

      return None

if __name__ == '__main__':

  p1 = Person('dredfsam','男','133665')

  p2 = Person('dream','女','r')

  p3 = Person('得分','男','sdf')

  personList = {}

  personList['p1']= p1

  personList['p2']= p2

  personList['p3']= p3

#  personList.append(p1)

#  personList.append(p2)

#  personList.append(p3)

  root = Converter.collectionToXML(personList)

  print Converter.getXmlString(root)

#  plist = (p1,p2,p3)#{'name':'sdf'}

#  print type(plist)

#  print type(plist),isinstance(plist, list)